This invention relates generally to purification of contaminated air on a large scale basis by exposure to the decomposing action of microwave energy generated plasma.
Because of air contamination by pollutants such as volatile organic compounds and chlorofluorocarbons, a considerable amount of technology and scientific data has been developed in recent years-regarding air purification involving microwave decomposition of air by plasma to produce a higher degree of ionization and dissociation of the pollutants as compared to other types of electrical excitation techniques. Further, because of a relatively high electron-to-gas temperature ratio involved in use of the microwave plasma technique for air purification, the plasma carrier gas remains moderately cool which is beneficial when the air is contaminated by carbon-based compounds.
Previous plasma processes for air purification involved corona discharge, dielectric barrier discharge and pulse glow discharge. Various disadvantages are associated with such known processes such as non-uniformity of operation, lack of control, energy loss, bulkiness of associated apparatus and complexity, etc.
It is therefore an important object of the present invention to provide a novel plasma processing system for air purification which avoids all of the aforementioned drawbacks of prior known plasma processes.